我正在尝试在我的musicLibrary数组中显示10个对象。每个对象都有其自己的艺术家名称,歌曲标题,比特率和歌曲总时间。
除“ BitRate = 0k”部分外,我的运行情况都很好。我的运行为我在阵列显示下的10个对象中的每个对象提供了BitRate = 0k。我希望每个对象的BitRate为{250、150、350、450、550、200、100、400、300、500}。
这些值都在我在iTunes类中设置的范围内。无论如何,如果这些值不在设定范围内,我应该收到“ Bad _ _ input”的输出。但是,我得到的是“ 0”。
我的代码中有两个单独的部分。
第一部分由不在数组中的四个对象组成。对于这四个,我显示它们,对其进行变异,显示它们,设置为默认值,然后显示。我的跑步很好。 (如果可能出现混淆,我不想删除此部分)。
第二部分是我的十个对象的数组。对于这一部分,我只需要显示数组中十个对象的数据。我的问题在这里,当我显示我的数组并且我的BitRate数据显示为0时。
对于这两个部分,我都在检查值是否在我设置的范围内。
值得一提的是,出于清洁起见,我可以删除其他代码(在代码中标记)吗?
我很困惑,因为我为BitRate编写的代码与我为其他实例成员(艺术家名称,歌曲名称,总时间)编写的代码基本相同,尽管变量名称不同。我似乎无法弄清楚是什么导致Eclipse显示“ 0”而不是我的值。
我是Java的初学者,所以希望您能提供一个简化的说明。
谢谢。
码:
public class Foothill {
public static void main(String [] args) {
//default constructor
iTunes Coldplay = new iTunes();
iTunes NorahJones = new iTunes();
iTunes Banks = new iTunes();
//constructor with parameters
iTunes JamesBay = new iTunes("Hold Back The River", "James Bay", 300, 240006);
//display objects immediately
System.out.print("Initial Display: " + '\n' + '\n' );
Coldplay.display();
NorahJones.display();
Banks.display();
JamesBay.display();
System.out.print("\n");
//mutate many of the objects' fields
Coldplay.setArtistName("Coldplay");
Coldplay.setKiloBits(275);
Coldplay.setSongTitle("Yellow");
Coldplay.setMilliSeconds(260000);
NorahJones.setArtistName("Norah Jones");
NorahJones.setKiloBits(75);
NorahJones.setSongTitle("Come Away With Me");
NorahJones.setMilliSeconds(190000);
Banks.setArtistName("Banks");
Banks.setKiloBits(175);
Banks.setSongTitle("Beggin for Thread");
Banks.setMilliSeconds(250000);
JamesBay.setArtistName("James Bay");
JamesBay.setKiloBits(375);
JamesBay.setSongTitle("Let it Go");
JamesBay.setMilliSeconds(251000);
//access object fields
Coldplay.getArtistName();
Coldplay.getSongTitle();
NorahJones.getArtistName();
NorahJones.getSongTitle();
Banks.getArtistName();
Banks.getSongTitle();
JamesBay.getArtistName();
JamesBay.getSongTitle();
//check to make sure mutator call is valid
System.out.print("Mutated Display: " + '\n' + '\n');
if (Coldplay.setSongTitle("Viva La Vida")){
Coldplay.display();
}
else { //can I delete this else?
System.out.println("Bad Artist Name input");
}
if (NorahJones.setSongTitle("Come Away With Me")){
NorahJones.display();
}
else { //can I delete this else?
System.out.println("Bad Artist Name input");
}
if (Banks.setSongTitle("Beggin For Thread")){
Banks.display();
}
else { //can I delete this else?
System.out.println("Bad Artist Name input");
}
if (JamesBay.setSongTitle("Let it Go")){
JamesBay.display();
System.out.print("\n");
}
else { //can I delete this else?
System.out.println("Bad Artist Name input");
}
//reset objects to default values
Coldplay.setDefaults();
NorahJones.setDefaults();
Banks.setDefaults();
JamesBay.setDefaults();
//display objects for the last time
System.out.print("Default Display: " + '\n' + '\n');
Coldplay.display();
NorahJones.display();
Banks.display();
JamesBay.display();
System.out.println("\n");
iTunes[] musicLibrary = new iTunes[10];
String[] originalArtist = new String [] {"The Script", "Tegan and Sara", "Bastille", "The Beatles", "Hozier", "Sam Smith", "Birdy", "George Ezra", "Haim", "Vance Joy"};
String[] nameArtist = new String[] {"The Script", "Tegan and Sara", "Bastille", "The Beatles", "Hozier", "Sam Smith", "Birdy", "George Ezra", "Haim", "Vance Joy"};
String[] originalSong = new String [] {"Superheroes", "Closer", "Flaws", "Let it Be", "Take Me to Church", "Lay Me Down", "Tee Shirt", "Budapest", "Falling", "Mess Is Mine"};
String[] titleSong = new String[] {"Superheroes", "Closer", "Flaws", "Let it Be", "Take Me to Church", "Lay Me Down", "Tee Shirt", "Budapest", "Falling", "Mess Is Mine"};
int[] originalBit = new int [] {250, 150, 350, 450, 550, 200, 100, 400, 300, 500}; //this is should be displayed as my BitRate
int[] rateBit = new int[] {250, 150, 350, 450, 550, 200, 100, 400, 300, 500}; //this is should be displayed as my BitRate
int[] originalTime = new int[] {270000, 200000, 210000, 240000, 242000, 246000, 145000, 202000, 250000, 208000};
int[] timeTotal = new int[] {270000, 200000, 210000, 240000, 242000, 246000, 145000, 202000, 250000, 208000};
System.out.print("Array Display: " + '\n' + '\n');
for (int i = 0; i < 10; i++) {
musicLibrary[i] = new iTunes();
if (musicLibrary[i].setArtistName(originalArtist[i])){
musicLibrary[i].setArtistName(nameArtist[i]);
}
else {
System.out.println("Bad Artist Name input");
}
if (musicLibrary[i].setSongTitle(originalSong[i])){
musicLibrary[i].setSongTitle(titleSong[i]);
}
else {
System.out.println("Bad Song Title input");
}
if (musicLibrary[i].setKiloBits(originalBit[i])){
musicLibrary[i].setKiloBits(rateBit[i]);
}
else {
System.out.println("Bad Bits Rate input");
}
if (musicLibrary[i].setMilliSeconds(originalTime[i])){
musicLibrary[i].setMilliSeconds(timeTotal[i]);
}
else {
System.out.println("Bad Song Length input");
}
musicLibrary[i].display();
}
}
}
class iTunes{
//private class instance members
private String name;
private String artist;
private int bitRate;
private double totalTime;
//public class static final constants
public static final int MIN_BITRATE = 64;
public static final int MAX_BITRATE = 705;
public static final int MIN_STR_LENGTH = 1;
public static final int MAX_STR_LENGTH = 128;
public static final int MIN_PLAY_TIME = 5000;
public static final int MAX_PLAY_TIME = 1000*60*60;
public static final int DEFAULT_BITRATE = 64;
public static final int DEFAULT_PLAY_TIME = 5000;
public static final String DEFAULT_STRING = "(undefined)";
//default constructor
public iTunes (){
name = "";
artist = "";
bitRate = 0;
totalTime = 0;
}
//constructor with parameters
iTunes (String songTitle, String artistName, int kiloBits, int milliSeconds) {
name = songTitle;
artist = artistName;
bitRate = kiloBits;
totalTime = milliSeconds;
}
//get/accessor and set/mutators for instance members
public String getSongTitle() {
return name;
}
public boolean setSongTitle(String songTitle) {
if (songTitle.length() > MIN_STR_LENGTH && songTitle.length() < MAX_STR_LENGTH){
name = songTitle;
return true;
}
return false;
}
public String getArtistName() {
return artist;
}
public boolean setArtistName(String artistName) {
if (artistName.length() > MIN_STR_LENGTH && artistName.length() < MAX_STR_LENGTH){
artist = artistName;
return true;
}
return false;
}
public int getKiloBits() {
return bitRate;
}
public boolean setKiloBits(int kiloBits) {
if (kiloBits > MIN_BITRATE && kiloBits < MAX_BITRATE){
bitRate = (kiloBits/1000);
return true;
}
return false;
}
public double getMilliSeconds() {
return totalTime;
}
public boolean setMilliSeconds(int milliSeconds) {
if (milliSeconds > MIN_PLAY_TIME && milliSeconds < MAX_PLAY_TIME){
totalTime = milliSeconds;
return true;
}
return false;
}
public String timeInMinutesAndSeconds(){
if (totalTime == 0.0){
return (totalTime + " minutes and " + totalTime + " seconds");
}
else {
int timeMinutes = (int) totalTime /60000;
int timeRemainder = (int) totalTime - timeMinutes * 60000;
int timeSeconds = timeRemainder/600;
return (timeMinutes + " minutes and " + timeSeconds + " seconds");
}
}
public String toString(){
return ("Title: " + name + " / Artist: " + artist + " / Playing Time: " + timeInMinutesAndSeconds() + " / BitRate: " + bitRate + "k");
}
public void setDefaults(){
name = DEFAULT_STRING;
artist = DEFAULT_STRING;
bitRate = DEFAULT_BITRATE;
totalTime = DEFAULT_PLAY_TIME;
}
public void display(){
System.out.println(toString());
}
}
跑:
初始显示:
标题:/艺术家:/播放时间:0.0分钟和0.0秒/比特率:0k
标题:/艺术家:/播放时间:0.0分钟和0.0秒/比特率:0k
标题:/艺术家:/播放时间:0.0分钟和0.0秒/比特率:0k
标题:忍住河/艺术家:詹姆斯湾/上场时间:4分钟0秒/比特率:300k
// Assignment表示仅变异一个或多个成员;我在这里离开了BitRate = 0k,所以这里应该是BitRate = 0k
突变显示:
标题:Viva La Vida /艺术家:Coldplay /播放时间:4分33秒/比特率:0k
标题:跟我走吧/歌手:诺拉·琼斯/上场时间:3分16秒/比特率:0k
标题:线程开始/艺术家:银行/播放时间:4分16秒/比特率:0k
标题:随它去吧/艺术家:詹姆斯贝(James Bay)/播放时间:4分18秒/比特率:0k
//这里的默认BitRate = 64k
默认显示:
标题:(未定义)/艺术家:(未定义)/播放时间:0分8秒/比特率:64k
标题:(未定义)/艺术家:(未定义)/播放时间:0分8秒/比特率:64k
标题:(未定义)/艺术家:(未定义)/播放时间:0分8秒/比特率:64k
标题:(未定义)/艺术家:(未定义)/播放时间:0分8秒/比特率:64k
//我的问题出现在数组显示中:我所有的BitRates = 0k
阵列显示:
标题:超级英雄/艺术家:剧本/播放时间:4分50秒/比特率:0k
标题:Closer /艺术家:Tegan and Sara /上场时间:3分33秒/比特率:0k
标题:缺陷/艺术家:巴士底狱/上场时间:3分50秒/比特率:0k
标题:顺其自然/艺术家:披头士乐队/上场时间:4分钟0秒/比特率:0k
标题:带我去教堂/艺术家:霍齐尔/上场时间:4分3秒/比特率:0k
标题:Lay Me Down /艺术家:Sam Smith /播放时间:4分10秒/比特率:0k
标题:T恤衫/艺术家:Birdy /上场时间:2分41秒/ BitRate:0k
标题:布达佩斯/艺术家:乔治·埃兹拉/上场时间:3分36秒/比特率:0k
标题:坠落/艺术家:Haim /播放时间:4分16秒/比特率:0k
标题:乱七八糟/艺术家:万斯·乔伊/上场时间:3分46秒/比特率:0k
最佳答案
问题是 :
bitRate =(千位数/ 1000)
这是在做整数除法,您的答案为0。
您可能应该将bitRate声明为double,然后执行以下操作:
bitRate =(kiloBits / 1000.00)。